Cardboard pallet

ABSTRACT

A cardboard pallet that offers improved strength, stiffness, durability, weight, and cost-effectiveness over cardboard pallets of the prior art is disclosed. The pallet consists of a top deck, internal cylindrical, triangular and hexagonal cores, side walls, and a bottom deck. The top sheet of cardboard is shaped in the form of an octagon and rests on internal triangular and hexagonal cores. The bottom sheet of cardboard is used to construct the side walls and bottom deck, and the bottom sheet of cardboard also has flaps that secure the bottom deck and sides to the top deck. The bottom deck has four holes for a pallet truck; the cardboard which is cut out to form the pallet truck holes are scored such that the cut out portions can form reinforcing tubular cores. The sides have openings that allow entry from four directions by a mechanized pallet handler.

CROSS REFERENCES

Continuation in Part of application Ser. No. 11/452,589 filed Jun. 14, 2006.

GOVERNMENTAL RIGHTS

None.

BACKGROUND OF THE INVENTION

Pallets are necessary to virtually all manufacturing and retail industries. Indeed, a global materials-handling industry relies exclusively on pallets to distribute goods from manufacturing sources to the ultimate purchaser. Products are now shipped on pallets that are capable of being moved by automated systems, by forklift in warehouse settings, or by pallet truck in retail settings. Pallets are available in a wide range of sizes and grades, and the design of a pallet is a function of at least five parameters, including strength, stiffness, durability, functionality, and price.

Traditional pallets are constructed of wood, as wood strikes a reasonable balance between the five pallet parameters. However, once wood pallets reach the end of their useful lives, they must be destroyed by pollution-emitting incineration or recycled into some other wood-based product. Wood pallets have other disadvantages, such as fasteners that are capable of damaging products, splinters, warping due to high initial moisture content, susceptibility to pest infestation, and high manufacturing tolerances that lead to wide variations in actual pallet size. Wood pallets still account for at least 90% of the 1.9 billion pallets in circulation in the United States.

More recently, paper-based pallets constructed from corrugated cardboard have begun to increase market pressure despite the fact that wood pallets are generally less expensive and more durable than typical cardboard pallets. The advantages of using paper materials for constructing pallets include lower weight than wood pallets and the ability to easily recycle the pallet once it reaches the end of its useful life. Cardboard pallets also offer the benefits of flat decks, resistance to insect damage, and low moisture content.

However, cardboard pallets of the prior art were not without disadvantages. When compared to wood pallets, cardboard pallets of the prior art were lacking in the parameters of strength, stiffness, and durability, which resulted in a low adoption rate in the materials-handling industry. To a large extent, the inadequacy of cardboard pallets in these areas was linked to inferior designs that lacked reinforcements at appropriate stress points on the pallet. For example, cardboard pallets are susceptible to damage by forklift and pallet truck operators when the tangs of the mechanized pallet handler do not enter the cardboard pallet properly. It is thus one object of the present invention to provide a cardboard pallet that is reinforced at entry points for mechanized pallet handlers.

One solution found in the prior art to address the insufficient strength, stiffness, and durability of cardboard pallets was to combine cardboard with traditional wood materials. For instance, U.S. Pat. No. 4,378,743 (the “'743 patent”) discloses a cardboard pallet that utilizes wood runners to purportedly increase strength and durability traditionally considered lacking in cardboard pallets. However, the use of wood in the '743 patent subjects it to the same criticisms of an all-wood pallet, such as weight, moisture damage to the cardboard, susceptibility to insect damage, and fastener-caused damage to the load. It is thus an object of the present invention to provide a cardboard pallet that provides strength, stiffness, and durability without incorporating traditional wood materials.

Cardboard pallets of the prior art also lacked sufficient strength and stiffness at the pallets' side walls. For instance, U.S. Pat. Nos. 4,085,847 (the “'847 patent”) and 6,070,726 (the “'726 patent”) disclose tray-type cardboard pallets whose side walls are comprised of overlapping cardboard flaps that are glued together. This design is believed to be deficient because it is susceptible to damage by a force applied to the interior of the pallet's side, such as a sudden lateral movement of the load or an impact by a misguided mechanized pallet handler tang. The '847 and '726 patents also disclose a method of installing a top deck on the patent, but these designs are easily compromised as both rely upon a top deck that simply rests on top of internal support structures. The design of the '847 and '726 patents lack the essential feature of securing the top deck to the sides of the pallet, and if the prior designs had included such feature then the resulting pallets would have had stronger sides and a stronger deck. It is thus a further objection of the present invention to provide a cardboard pallet that has sides that are less susceptible to damage caused by forces applied to the interior of the pallet's side walls and that secures the top deck to the sides of the pallet.

Still another method of increasing the strength, stiffness, and durability of cardboard pallets involves using many layers of cardboard to provide added strength. For example, U.S. Pat. No. 5,465,672 (the “'672 patent”) discloses a pallet that has four cardboard layers. The '672 patent serves as an inelegant solution to the problem posed by the lack of strength, stiffness, and durability in cardboard pallets of the prior art, as the amount of cardboard used detracts from the primary advantage of a cardboard pallet of low weight. The amount of cardboard used in the '672 patent also renders it essentially unmarketable due to the even higher cost of construction than a typical cardboard pallet and the current low cost of wood pallets. It is thus an object of the present invention to provide a cardboard pallet that substantially requires only a top and bottom layer.

As shown by the deficiencies of the prior art discussed above, there is a need in the materials handling industry for a cardboard pallet that offers strength, stiffness, durability, and price that rivals that of a wood pallet. It is thus an object of the present invention to provide a strong, stiff, durable, cost-effective, and recyclable cardboard pallet.

The apparatus in accordance with the present invention provides an internally-reinforced cardboard pallet that conserves construction materials, provides commercially acceptable strength, load bearing capabilities, stiffness, and durability, and is easily constructed at a commercially reasonable cost.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a two-layer, internally-reinforced, four-way accessible cardboard pallet that utilizes unique hexagonal internal cores to provide commercially adequate strength, stiffness, and durability. The hexagonal cores provide an advantage over the square internal cores set forth by the prior art, as the hexagonal cores provide more strength and rigidity to the pallet. Hexagonal cores also increase the stiffness of the cardboard pallet, as hexagonal cores are less susceptible to shear forces than rectangular cores; that is, a rectangular core deforms far more easily than a hexagonal core when a force is applied to the long side of the core. The hexagonal cores also provide an advantage in strength and design in that a misguided mechanized pallet handler tang that impacts the core does not strike a corner of the hexagonal core, but is more likely redirected off a face of the hexagonal core. Further, even if one corner of the hexagonal core is compromised, the hexagonal core has more support corners available to continue supporting the pallet structure.

The top deck of the cardboard pallet is essentially a solid octagon of cardboard. The original starting medium forming the bottom deck of the cardboard pallet has a plurality of scores that allows it to be folded into what eventually becomes the octagonal bottom deck, side walls, and flaps that overlap the top deck. Triangular and hexagonal cores are secured to the bottom deck, and the top deck is secured on top of the cores. Then, the flaps are secured to the top deck. Each of four side walls of the pallet are pre-scored and pre-cut such that two openings are made for mechanized pallet handler tangs by folding a reinforcing flap up into the interior of the pallet and securing it to the bottom of the top deck.

The first preferred embodiment is not a regular octagon. That is, two of the four side walls of the pallet having the openings are not wide enough to accommodate a standard mechanized pallet handler tang opening. Therefore, the remaining four side walls are notched to create a uniform mechanized pallet handler tang opening from all four directions. Like the opening itself, the notch is also formed by folding a reinforcing flap up into the interior of the pallet and securing it to the bottom of the top deck.

The bottom deck preferentially has four openings designed to allow the wheels of a pallet truck to make contact with the floor. Each of the cutouts forming the four openings for pallet truck wheels is preferentially scored such that the excess material from the cutout can be used as construction material for tubular cores. The tubular cores are designed to be inserted within the interior of the triangular and hexagonal cores or at mechanized pallet handler tang entry points, which serves to strengthen and stiffen the cardboard pallet.

The second preferred embodiment lacks notched side walls. That is, four side have walls with openings for mechanized pallet handler tangs, while the remaining four sides have no walls. The second preferred embodiment utilizes tubular cores created from the pallet truck wheel cutouts instead of triangular cores to support and strengthen the top deck. The second preferred embodiment is intended for use in applications requiring lower strength or less weight.

Optionally, a water resistant sealant can be applied to the cardboard pallet to protect from moisture damage. The sealant is preferably applied in a light coat to keep the total weight of the cardboard pallet down and to allow the treated cardboard pallet to still be recycled.

These and other advantages will become apparent from the following detailed description which, when viewed in light of the accompanying drawings, disclose the embodiments of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the first preferred embodiment of the present invention.

FIG. 2 is a schematic view of the bottom cardboard sheet that forms the bottom deck, sides, and flaps of the present invention.

FIG. 3 is a perspective view of a triangular core of the present invention.

FIG. 4 is a perspective view of a hexagonal core of the present invention.

FIG. 5 is an exploded perspective view of the cardboard pallet of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to FIGS. 1-5, the cardboard pallet 101 of the present invention is preferably constructed using a die cutting tool programmed to use schematics to score and cut the bottom sheet 201, triangular cores 301, hexagonal cores 401, and top deck 501 with precision. The components are then assembled by hand or by machine and secured into place.

Referring now to FIG. 2, bottom sheet 201 is cut from an original starting medium sheet of cardboard. Bottom sheet 201 is comprised of an octagonal bottom deck 203, two first tabs 205, two second tabs 207, and four third tabs 209. First tabs 205 are further comprised of first tab score lines 211, first tab opening cut lines 213, first tab reinforcement score lines 215, and first tab flap score lines 217. Second tabs 207 are further comprised of second tab score lines 219, second tab opening cut lines 221, second tab reinforcement score lines 223, and second tab flap score lines 225. Third tabs 207 may be further comprised of third tab score lines 227, third tab opening cut lines 229, third tab reinforcement score lines 231, and third tab flap score lines 233.

To construct the pallet, a plurality of hexagonal cores 401 are glued into a plurality of first tab hexagonal core positions 235 adjacent to first tabs 205 and a plurality of second tab hexagonal core positions 237 adjacent to second tabs 207. A hexagonal core 401 is also glued into center hexagonal core position 239. A plurality of triangular cores 301 are glued into a plurality of triangular core positions 241 adjacent to third tabs 209.

After the cores are secured into place, top deck 501 is aligned with bottom deck 202 and glued to triangular cores 301 and hexagonal cores 401. First tabs 205 are folded along first tab score lines 211 and glued to adjacent hexagonal cores 401 and the thin edge of top deck 501, which forms a plurality of first side walls 243. Second tabs 207 are folded along second tab score lines 219 and glued to adjacent hexagonal cores 401 and the thin edge of top deck 501, which forms a plurality of second side walls 245. Third tabs 207 may be folded along third tab score lines 227 and glued to adjacent triangular cores 301 and the thin edge of top deck 501, which forms a plurality of third side walls 247.

Once side walls 243, 245, and 247 are constructed, first tabs 205 are folded along first tab flap score lines 217 to form first tab flaps 249. First tab flaps 249 are glued to the top of top deck 501. Second tabs 207 are folded along second tab flap score lines 225 to form second tab flaps 251. Second tab flaps 251 are glued to the top of top deck 501. Third tabs 207 are folded along third tab flap score lines 233 to form third tab flaps 253. Third tab flaps 253 are glued to the top of top deck 501.

After top deck 501 is secured to tab flaps 249, 251, and 253, first tabs 205 are folded along first tab reinforcement score lines 215 to form first tab reinforcements 255. First tab reinforcements 255 are glued to the bottom of top deck 501. Second tabs 207 are folded along second tab reinforcement score lines 223 to form second tab reinforcements 257. Second tab reinforcements 257 are glued to the bottom of top deck 501. Third tabs 207 are folded along third tab reinforcement score lines 231 to form third tab reinforcements 259. Third tab reinforcements 259 may be glued to the bottom of top deck 501. When tab reinforcements 255, 257, and 259 are folded and secured into place, mechanized pallet handler tang openings 103 become visible.

Optionally, bottom deck 207 allows passage of the wheels of a pallet truck with a plurality of pallet truck cutouts 261, which are formed by pallet truck cutout cut lines 263. Pallet truck cutouts 261 are scored along pallet truck cutout score lines 265 such that the pallet truck cutouts 261 can be folded into tubular cores 503, shown in FIG. 5. Tubular cores 503 are glued to top deck 501 or bottom deck 203 at mechanized pallet handler tang entry points 267, 269, 271, and/or 273 or in the interior 275 of triangular cores 301 or hexagonal cores 401. Regardless of where tubular cores 503 are positioned, tubular cores 503 serve to strengthen and stiffen cardboard pallet 101, which in turn increases the durability of cardboard pallet 101.

The first preferred embodiment of the present invention forms a non-regular octagon. In the first preferred embodiment, first tab hexagonal core positions 235 are placed such that a flat side of hexagonal cores 401 communicates with first side walls 243, while second tab hexagonal core positions 237 are placed such that only a single vertex of hexagonal cores 401 communicates with second side walls 245.

Optionally, the cardboard pallet 101 of the present invention can form a regular octagon. In the regular octagon embodiment, first side tabs 203 and second side tabs 205 are identical. Hexagonal core positions 235 and 237 are placed such that only a single vertex of hexagonal cores 401 communicates with first side walls 243 and second side walls 245.

The second preferred embodiment lacks third tabs 207, which lowers overall weight and reduces the amount of starting material required to construct cardboard pallet 101 with greatly sacrificing strength. The second preferred embodiment utilizes a plurality of hexagonal cores 401 but not triangular cores 301. Instead of triangular cores 301, the second preferred embodiment uses a plurality of tubular cores 503 inserted at in what would be the interior 275 of triangular cores 301 were triangular cores 301 used in the second preferred embodiment. Optionally, two or more tubular cores 501 can be placed substantially along the path marked by triangular core positions 241.

In accordance with the present invention, a cardboard pallet provides improved strength, stiffness, and durability while weighing less and creating less excess materials. However, it should be clear that the present invention is not to be construed as limited to the forms shown, which are to be considered illustrative rather than restrictive. 

1. An octagonal cardboard pallet designed to allow for multiple internal support members, said pallet having at least eight openings that allow pallet-handling machine entry from four directions, comprising: A bottom sheet forming a bottom deck, having not less than eight tabs with first tab score lines such that the tabs can be folded along the first tab score lines to form at least eight side walls that are substantially perpendicular to the bottom deck, said tabs also having second tab score lines such that the tabs can be folded along the second tab score lines to form one or more adhesive connection surface(s); At least five internal cores having at least six sides which communicate with and are secured to the bottom deck; At least four internal triangular cores having not more than three sides which communicate with and are secured to the bottom deck; At least nine internal cylindrical cores which communicate with and are secured to the bottom deck; At least four rectangular openings cut into the bottom sheet and which are spaced equidistant from one another; and, A top sheet forming a top deck having the same octagonal shape as the bottom deck, which is aligned with the bottom deck and secured with adhesive to the hexagonal, triangular, and cylindrical cores, as well as the adhesive connection surfaces.
 2. The cardboard pallet of claim 1, further comprising the application of a water resistant sealant to the cardboard pallet.
 3. The cardboard pallet of claim 1, wherein the eight openings that allow pallet-handling machine entry from four directions are created by cutting a U-shaped design into the tabs to create an opening whereby the remaining cardboard may pivot upward along a score line to serve as an additional adhesive surface with which to connect the top sheet. 